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do humidifiers actually work?

we install quite a few general air 1042 humidifiers at work.home owners always ask us if they work well and i always reply yes,that is the model i have at home.my boss on the other hand says the flow throughs are crap and a steam type though expensive is the only way to go.so i went out and bought a hygrometer for my house and the humidity varies bettween 34% and 40% with the humidifier on.so i turn humidifier off and low and behold the readings remain basically the same.i do have an older home that is by no means air tight and i have no HRV.the heating system is forced air hi-eff gas.just wondered if any of you other guys have actually monitored your humidity readings????????

What are you expecting from your humidifier? 35-40%RH is as high as you should set the humidifier during cold weather. Watch you windows for slight condensation low in the corners. Any dripping on the sills is a sign of excess moisture in the home. Wait until the outdoor dew points hang around 0^F for a week. The number of occupants and the air change rate determine the %RH you will end with. A +3,000 sqft. with an air change in 4-5 hours, <10^F outdoor dew points needs 2-4 lbs. of moisture per hour to maintain 68^F, 35-40%RH inside. Figure .5 lb. of moisture per hour from an occupant. Two occupants in the home 12 hours per day need a good humidifier function most of the time. For a humidifier to evaporate moisture, you need +500 ft of velocity flowing through the pad of the humidifier. By pass humidifiers with a fan on low does not get enough flow through the pad. Limiting the humdifier to the run time of the furnace heating also limits the humidifier.
I suggest a 4-6" duct fan connected to the humidifier for real humidification from a pad humidifier. Or a fan humidifier in the supply duct with the furnace fan on low when humidification is needed.
Keep up posted. You are on the right track with monitioring your humidifier to work well. High air flow, a wet pad, and adequate hours usually will get you all the moisture you need.
Regards TB

I've tried different solutions and am currently using a $10 console humidifier that I bought at a garage sale. It's an 80's Kenmore that uses a rotating belt instead of the paper pads that don't seem to last.

thanks for the detailed reply teddy bear.my humidifier is interlocked with furnace so it only runs with a call for heat.i had this sucker for several years but never monitored it before.just set it a 40% and forget it.right now im at 35% humidity but its fairly mild out,right around the freezing mark.if we ever get any cold weather i will be able to see what this sucker will do.

A tight home will not need a humidifier! If a customer complains of low humidity they need their envelope tightened up. Once this is done and done well, they will need mechanical ventilation to DE-humidify. Lots of experience doing this and reducing energy consumption. One quick way to eliminate several BIG holes in a home is change the furnace to sealed combustion and close up the combustion/ ventilation holes the old FAU required. Make money and make a customer very happy.

we install quite a few general air 1042 humidifiers at work.home owners always ask us if they work well and i always reply yes,that is the model i have at home.my boss on the other hand says the flow throughs are crap and a steam type though expensive is the only way to go.so i went out and bought a hygrometer for my house and the humidity varies bettween 34% and 40% with the humidifier on.so i turn humidifier off and low and behold the readings remain basically the same.i do have an older home that is by no means air tight and i have no HRV.the heating system is forced air hi-eff gas.just wondered if any of you other guys have actually monitored your humidity readings????????

cheers

Is the humidifier wired up to only run while the burners are on, or only while the fan is on. Or does it run anytime the humidistat calls for it to run.